TR250 and TR6 Glove Box Companion
YOUR ENGINE OIL MAY BE RUINING YOUR ENGINE!
“Modern Oils Without Zinc and Phosphorous Are Not Suitable
for Older Engines with Flat Valve Tappets”
New car manufacturers have worked with commercial oil
companies to remove zinc and phosphorous from engine oils. This
is desirable to new car manufacturers, as zinc and phosphorous
cause early failure of catalytic converters. You may find some older
oils designated "SL." and these still retain some zinc and
phosphorous. Later oils, which are about all you can find in auto
parts stores now, are designated "SM," and these oils do not have
the zinc and phosphorous critical to the life of camshafts and flat
valve tappets fitted along with high valve spring pressures. New
car manufacturers have compensated for low zinc and phosphorous
by fitting roller tappets with lower spring pressures. In case you
don't know, all of the engines in models serviced by TRF use flat
TRF now offers two ways for our customers to provide the zinc
and phosphorous required by classic Triumph sports car engines.
One way is to use the oil you can buy locally but to add a product known as ZDDPlus.
This product replaces the zinc and phosphorous that your engine requires. You will
find ZDDPlus listed below. The second way to solve the problem is to purchase Penn
Grade High Performance Motor Oil which is made in the old Kendall and Amalie
refinery in Bradford, Pennsylvania. This oil is especially formulated for classic car
engines, and it contains the zinc and phosphorous your engine requires. You will find
Penn Grade oils listed on the previous page.
ZDDPlus Engine Oil Additive;
restores levels of zinc and phosphorous
required for long life of engines with flat